In general, an interposer is an electrical interface having means for routing between one socket, contact, or connection to another socket, contact, or connection. The purpose of an interposer is to spread an electrical connection to a wider pitch or to reroute an electrical connection to a different connection.
Interposers are often used as connectors in the field of micro-electro mechanical systems (MEMS). MEMS, also known in the art as “micromachines,” are typically made up of individual components and generally range in size from 20 micrometers to a millimeter. As one example, interposers are often used in MEMS style probe cards designed to test and validate the circuitry of semiconductor wafers. Probe cards typically include a printed circuit board (PCB) and a probe head consisting of a substrate and probe contactors. An interposer can be positioned between the PCB and the probe head and have a plurality of pins that serve as electrical interconnects between the contacts of the PCB and the corresponding contacts on the substrate which are in operable communication with the probe contactors.
One problem of current interposers is that the vertical compression associated with the probe heads contacting the semiconductor during “touchdown” applies mechanical stress on the interposer pins which can lead to damage and malfunction. Accordingly new interposer pins are needed to help alleviate the mechanical stresses associated with interconnecting two electrical devices.